\documentclass{article}
\usepackage{amssymb,amsmath,amscd,concmath}
\pagestyle{empty}
\begin{document}
\begin{equation*}
You have $\epsilon$ cows, where
\[
  \epsilon = \sqrt\py\div\int_0^\inf e^{-x^2} dx
\]
\end{equation*}
\end{document}
